Extension cord



FIG. 1 is a top, rear perspective view of an extension cord showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a bottom view thereof;

FIG. 7 is a top view thereof; and,

FIG. 8 is a bottom, front perspective view thereof.

The broken lines in the drawings illustrate portions of the extension cord which form no part of the claimed design. 

CLAIM The ornamental design for an extension cord, as shown and described. 